The Design Of The ECG Data Acquisition System Based On The USB Protocol And The Study Of The Method For Deriving Respiratory Signal From ECG Signal

Respiration is the exchanging process of gas between human's body and the environment. It is the important physiological process of human. The detection of the respiration is also a important constitute of the modern iatrical ward technology. The respiratory frequency is a significant parameter of the respiration. We can obtain many hidden information through analysis of it. For the detection for the respiratory frequency is easy to realize, it is the primary object for the existing respiratory detecting equipment.Plentiful clinical data showed that the respiration would cause the change of the ECG. Morphologic beat-to-beat variations can beobserved in the ECG during the respiratory cycle as caused by chest movements and changes in the position of the heart. During this cycle the electrical axis of the heart, describing the main direction of the electrical wave propagation, is subjected to rotation which causes variations in QRS morphology.Adaptive filtering is the signal processing method developed from recent 30 years. It is widely used in system identification, noise cancellation, channel equalization, predictive coding, etc. It has been validate that the noise component of the R-R interval series and of the R-wave amplitude series is not correlated with each other. And they are not correlated with the respiratory signal either.This thesis thoroughly studied the domestic and overseas research on the respiratory signal detecting methods. Base on the ECG periodicity variations caused by the respiratory activity, we designed a new method to obtain the respiratory signal used the adaptive filtering technology.The research work has been carried out from the three aspects in this thesis: Designed the ECG data acquisition system. In this system, I designed the MCU software, the hardware of USB data transfer unit and the USB device driver. Designed the experiment scheme to obtain the ECGsignal. Abstracted the R-R interval series and the R-wave amplitude series; analyzed the two signals' quality and...